Processing technologies for gold-telluride ores
2016-9-12 Generally, gold ores can be classified into two categories: the ‘free milling’ and ‘refractory’ ores. Free milling ores are those that require only conventional physical pre-treatment, such as grinding and sulfide flotation, to liberate the free gold and obtain a concentrate for further cyanidation. Re-fractory ores, however, require fine grinding and a further pre-treatment step, such as roasting and pressure oxidation, to render the gold ores amenable to extraction. Usually, gold telluride ores appear to be refractory as they are always as-sociate with pyrite and other sulfides. This would ‘lock’ the gold and give rise to elevated cyanide consumption. For this reason, oxidative pre-treatments are generally conducted to improve gold